This is a lovely book, beautifully illustrated in watercolours, about a boy whose younger brother is "special" (he appears to be autistic, but this isn't specified). Sammy seems to act and be treated differently, which leads to his brother's slightly resentful observations on how he doesn't behave "normally". This is quite an issue in a household with a developmentally handicapped child, and the book represents the older brother's understandable resentment without putting him in the wrong. But Sammy unexpectedly turns the tables on his brother, and the two go off together sometimes to do the things that Sammy likes, which his brother finds opens up a whole new range of experiences and sensations he had never looked for before.
I would recommend this book for anyone with a developmentally handicapped or "different" child in the family, and I think that all schools should stock it as a matter of course.